sh: Make PAGE_OFFSET configurable.

nommu needs to be able to shift PAGE_OFFSET, so we switch it to a
non-user-visible CONFIG_PAGE_OFFSET and use that in the few places
where it matters.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

5 files changed, 35 insertions, 29 deletions

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 07d6d699e9c2..035df7fb2237 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -238,32 +238,6 @@ endchoice
 
 source "arch/sh/mm/Kconfig"
 
-config MEMORY_START
-        hex "Physical memory start address"
-        default "0x08000000"
-        ---help---
-          Computers built with Hitachi SuperH processors always
-          map the ROM starting at address zero.  But the processor
-          does not specify the range that RAM takes.
-
-          The physical memory (RAM) start address will be automatically
-          set to 08000000. Other platforms, such as the Solution Engine
-          boards typically map RAM at 0C000000.
-
-          Tweak this only when porting to a new machine which does not
-          already have a defconfig. Changing it from the known correct
-          value on any of the known systems will only lead to disaster.
-
-config MEMORY_SIZE
-        hex "Physical memory size"
-        default "0x00400000"
-        help
-          This sets the default memory size assumed by your SH kernel. It can
-          be overridden as normal by the 'mem=' argument on the kernel command
-          line. If unsure, consult your board specifications or just leave it
-          as 0x00400000 which was the default value before this became
-          configurable.
-
 config CF_ENABLER
         bool "Compact Flash Enabler support"
         depends on SH_ADX || SH_SOLUTION_ENGINE || SH_UNKNOWN || SH_CAT68701 || SH_SH03
diff --git a/arch/sh/boot/compressed/Makefile b/arch/sh/boot/compressed/Makefile
index 75a6876bf6c6..7074267c01b7 100644
--- a/arch/sh/boot/compressed/Makefile
+++ b/arch/sh/boot/compressed/Makefile
@@ -18,9 +18,10 @@ endif
 # Assign dummy values if these 2 variables are not defined,
 # in order to suppress error message.
 #
+CONFIG_PAGE_OFFSET      ?= 0x80000000
 CONFIG_MEMORY_START     ?= 0x0c000000
 CONFIG_BOOT_LINK_OFFSET ?= 0x00800000
-IMAGE_OFFSET := $(shell printf "0x%8x" $$[0x80000000+$(CONFIG_MEMORY_START)+$(CONFIG_BOOT_LINK_OFFSET)])
+IMAGE_OFFSET := $(shell printf "0x%8x" $$[$(CONFIG_PAGE_OFFSET)+$(CONFIG_MEMORY_START)+$(CONFIG_BOOT_LINK_OFFSET)])
 
 LDFLAGS_vmlinux := -Ttext $(IMAGE_OFFSET) -e startup -T $(obj)/../../kernel/vmlinux.lds
 
diff --git a/arch/sh/kernel/vmlinux.lds.S b/arch/sh/kernel/vmlinux.lds.S
index 3f3e1e0735f5..eb860c51c697 100644
--- a/arch/sh/kernel/vmlinux.lds.S
+++ b/arch/sh/kernel/vmlinux.lds.S
@@ -13,7 +13,7 @@ OUTPUT_ARCH(sh)
 ENTRY(_start)
 SECTIONS
 {
-  . = 0x80000000 + CONFIG_MEMORY_START + CONFIG_ZERO_PAGE_OFFSET;
+  . = CONFIG_PAGE_OFFSET + CONFIG_MEMORY_START + CONFIG_ZERO_PAGE_OFFSET;
   _text = .;                    /* Text and read-only data */
   text = .;                     /* Text and read-only data */
   .empty_zero_page : {
diff --git a/arch/sh/mm/Kconfig b/arch/sh/mm/Kconfig
index 9064dfc91e6d..f25903aa607b 100644
--- a/arch/sh/mm/Kconfig
+++ b/arch/sh/mm/Kconfig
@@ -161,6 +161,37 @@ config MMU
           turning this off will boot the kernel on these machines with the
           MMU implicitly switched off.
 
+config PAGE_OFFSET
+        hex
+        default "0x80000000" if MMU
+        default "0x00000000"
+
+config MEMORY_START
+        hex "Physical memory start address"
+        default "0x08000000"
+        ---help---
+          Computers built with Hitachi SuperH processors always
+          map the ROM starting at address zero.  But the processor
+          does not specify the range that RAM takes.
+
+          The physical memory (RAM) start address will be automatically
+          set to 08000000. Other platforms, such as the Solution Engine
+          boards typically map RAM at 0C000000.
+
+          Tweak this only when porting to a new machine which does not
+          already have a defconfig. Changing it from the known correct
+          value on any of the known systems will only lead to disaster.
+
+config MEMORY_SIZE
+        hex "Physical memory size"
+        default "0x00400000"
+        help
+          This sets the default memory size assumed by your SH kernel. It can
+          be overridden as normal by the 'mem=' argument on the kernel command
+          line. If unsure, consult your board specifications or just leave it
+          as 0x00400000 which was the default value before this became
+          configurable.
+
 config 32BIT
         bool "Support 32-bit physical addressing through PMB"
         depends on CPU_SH4A
diff --git a/include/asm-sh/page.h b/include/asm-sh/page.h
index 51d7281a546a..1b3cfd165a66 100644
--- a/include/asm-sh/page.h
+++ b/include/asm-sh/page.h
@@ -84,7 +84,7 @@ typedef struct { unsigned long pgprot; } pgprot_t;
 #define __MEMORY_START          CONFIG_MEMORY_START
 #define __MEMORY_SIZE           CONFIG_MEMORY_SIZE
 
-#define PAGE_OFFSET             (0x80000000UL)
+#define PAGE_OFFSET             CONFIG_PAGE_OFFSET
 #define __pa(x)                 ((unsigned long)(x)-PAGE_OFFSET)
 #define __va(x)                 ((void *)((unsigned long)(x)+PAGE_OFFSET))